FACE/CORE DEBONDING CHARACTERIZATION OF FOAM AND HONEYCOMB CORE SANDWICH STRUCTURES USING SINGLE CANTILEVER BEAM TESTING METHOD

摘要

Single Cantilever Beam (SCB) testing was conducted on foam and honeycomb core sandwich specimens to predict the fracture toughness and bonding strength. Adhesion characteristics can also be identified between facesheet and core materials conducting SCB test on precracked specimen. Disbonding under combined tensile and shear loading may involve failure modes such as kinking and cell buckling. Modified Beam Theory (MBT) method specifies required parameters to generate a least square plot based on experimentally determined compliance and disbond length obtained during the SCB test. Interfacial fracture toughness G_c, enumerated by following recommended data reduction methodologies, required to predict minimum G_c to initiate disbond growth. Finally, experimental compliance was compared with elastic foundation stiffness compliance to verify the performance of the test. Good agreement between two compliance solutions validates the accuracy of the SCB test.